arch/s390/kernel/crash_dump.c - LeafOS-Devices/android_kernel_samsung_gta4xl - Gitiles

 /*
  * S390 kdump implementation
  *
  * Copyright IBM Corp. 2011
  * Author(s): Michael Holzheu <holzheu@linux.vnet.ibm.com>
  */

 #include <linux/crash_dump.h>
 #include <asm/lowcore.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/gfp.h>
 #include <linux/slab.h>
 #include <linux/bootmem.h>
 #include <linux/elf.h>
 #include <asm/ipl.h>

 #define PTR_ADD(x, y) (((char *) (x)) + ((unsigned long) (y)))
 #define PTR_SUB(x, y) (((char *) (x)) - ((unsigned long) (y)))
 #define PTR_DIFF(x, y) ((unsigned long)(((char *) (x)) - ((unsigned long) (y))))

 /*
  * Copy one page from "oldmem"
  *
  * For the kdump reserved memory this functions performs a swap operation:
  *  - [OLDMEM_BASE - OLDMEM_BASE + OLDMEM_SIZE] is mapped to [0 - OLDMEM_SIZE].
  *  - [0 - OLDMEM_SIZE] is mapped to [OLDMEM_BASE - OLDMEM_BASE + OLDMEM_SIZE]
  */
 ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
 			 size_t csize, unsigned long offset, int userbuf)
 {
 	unsigned long src;

 	if (!csize)
 		return 0;

 	src = (pfn << PAGE_SHIFT) + offset;
 	if (src < OLDMEM_SIZE)
 		src += OLDMEM_BASE;
 	else if (src > OLDMEM_BASE &&
 		 src < OLDMEM_BASE + OLDMEM_SIZE)
 		src -= OLDMEM_BASE;
 	if (userbuf)
 		copy_to_user_real((void __force __user *) buf, (void *) src,
 				  csize);
 	else
 		memcpy_real(buf, (void *) src, csize);
 	return csize;
 }

 /*
  * Copy memory from old kernel
  */
 static int copy_from_oldmem(void *dest, void *src, size_t count)
 {
 	unsigned long copied = 0;
 	int rc;

 	if ((unsigned long) src < OLDMEM_SIZE) {
 		copied = min(count, OLDMEM_SIZE - (unsigned long) src);
 		rc = memcpy_real(dest, src + OLDMEM_BASE, copied);
 		if (rc)
 			return rc;
 	}
 	return memcpy_real(dest + copied, src + copied, count - copied);
 }

 /*
  * Alloc memory and panic in case of ENOMEM
  */
 static void *kzalloc_panic(int len)
 {
 	void *rc;

 	rc = kzalloc(len, GFP_KERNEL);
 	if (!rc)
 		panic("s390 kdump kzalloc (%d) failed", len);
 	return rc;
 }

 /*
  * Get memory layout and create hole for oldmem
  */
 static struct mem_chunk *get_memory_layout(void)
 {
 	struct mem_chunk *chunk_array;

 	chunk_array = kzalloc_panic(MEMORY_CHUNKS * sizeof(struct mem_chunk));
 	detect_memory_layout(chunk_array);
 	create_mem_hole(chunk_array, OLDMEM_BASE, OLDMEM_SIZE, CHUNK_CRASHK);
 	return chunk_array;
 }

 /*
  * Initialize ELF note
  */
 static void *nt_init(void *buf, Elf64_Word type, void *desc, int d_len,
 		     const char *name)
 {
 	Elf64_Nhdr *note;
 	u64 len;

 	note = (Elf64_Nhdr *)buf;
 	note->n_namesz = strlen(name) + 1;
 	note->n_descsz = d_len;
 	note->n_type = type;
 	len = sizeof(Elf64_Nhdr);

 	memcpy(buf + len, name, note->n_namesz);
 	len = roundup(len + note->n_namesz, 4);

 	memcpy(buf + len, desc, note->n_descsz);
 	len = roundup(len + note->n_descsz, 4);

 	return PTR_ADD(buf, len);
 }

 /*
  * Initialize prstatus note
  */
 static void *nt_prstatus(void *ptr, struct save_area *sa)
 {
 	struct elf_prstatus nt_prstatus;
 	static int cpu_nr = 1;

 	memset(&nt_prstatus, 0, sizeof(nt_prstatus));
 	memcpy(&nt_prstatus.pr_reg.gprs, sa->gp_regs, sizeof(sa->gp_regs));
 	memcpy(&nt_prstatus.pr_reg.psw, sa->psw, sizeof(sa->psw));
 	memcpy(&nt_prstatus.pr_reg.acrs, sa->acc_regs, sizeof(sa->acc_regs));
 	nt_prstatus.pr_pid = cpu_nr;
 	cpu_nr++;

 	return nt_init(ptr, NT_PRSTATUS, &nt_prstatus, sizeof(nt_prstatus),
 			 "CORE");
 }

 /*
  * Initialize fpregset (floating point) note
  */
 static void *nt_fpregset(void *ptr, struct save_area *sa)
 {
 	elf_fpregset_t nt_fpregset;

 	memset(&nt_fpregset, 0, sizeof(nt_fpregset));
 	memcpy(&nt_fpregset.fpc, &sa->fp_ctrl_reg, sizeof(sa->fp_ctrl_reg));
 	memcpy(&nt_fpregset.fprs, &sa->fp_regs, sizeof(sa->fp_regs));

 	return nt_init(ptr, NT_PRFPREG, &nt_fpregset, sizeof(nt_fpregset),
 		       "CORE");
 }

 /*
  * Initialize timer note
  */
 static void *nt_s390_timer(void *ptr, struct save_area *sa)
 {
 	return nt_init(ptr, NT_S390_TIMER, &sa->timer, sizeof(sa->timer),
 			 KEXEC_CORE_NOTE_NAME);
 }

 /*
  * Initialize TOD clock comparator note
  */
 static void *nt_s390_tod_cmp(void *ptr, struct save_area *sa)
 {
 	return nt_init(ptr, NT_S390_TODCMP, &sa->clk_cmp,
 		       sizeof(sa->clk_cmp), KEXEC_CORE_NOTE_NAME);
 }

 /*
  * Initialize TOD programmable register note
  */
 static void *nt_s390_tod_preg(void *ptr, struct save_area *sa)
 {
 	return nt_init(ptr, NT_S390_TODPREG, &sa->tod_reg,
 		       sizeof(sa->tod_reg), KEXEC_CORE_NOTE_NAME);
 }

 /*
  * Initialize control register note
  */
 static void *nt_s390_ctrs(void *ptr, struct save_area *sa)
 {
 	return nt_init(ptr, NT_S390_CTRS, &sa->ctrl_regs,
 		       sizeof(sa->ctrl_regs), KEXEC_CORE_NOTE_NAME);
 }

 /*
  * Initialize prefix register note
  */
 static void *nt_s390_prefix(void *ptr, struct save_area *sa)
 {
 	return nt_init(ptr, NT_S390_PREFIX, &sa->pref_reg,
 			 sizeof(sa->pref_reg), KEXEC_CORE_NOTE_NAME);
 }

 /*
  * Fill ELF notes for one CPU with save area registers
  */
 void *fill_cpu_elf_notes(void *ptr, struct save_area *sa)
 {
 	ptr = nt_prstatus(ptr, sa);
 	ptr = nt_fpregset(ptr, sa);
 	ptr = nt_s390_timer(ptr, sa);
 	ptr = nt_s390_tod_cmp(ptr, sa);
 	ptr = nt_s390_tod_preg(ptr, sa);
 	ptr = nt_s390_ctrs(ptr, sa);
 	ptr = nt_s390_prefix(ptr, sa);
 	return ptr;
 }

 /*
  * Initialize prpsinfo note (new kernel)
  */
 static void *nt_prpsinfo(void *ptr)
 {
 	struct elf_prpsinfo prpsinfo;

 	memset(&prpsinfo, 0, sizeof(prpsinfo));
 	prpsinfo.pr_sname = 'R';
 	strcpy(prpsinfo.pr_fname, "vmlinux");
 	return nt_init(ptr, NT_PRPSINFO, &prpsinfo, sizeof(prpsinfo),
 		       KEXEC_CORE_NOTE_NAME);
 }

 /*
  * Initialize vmcoreinfo note (new kernel)
  */
 static void *nt_vmcoreinfo(void *ptr)
 {
 	char nt_name[11], *vmcoreinfo;
 	Elf64_Nhdr note;
 	void *addr;

 	if (copy_from_oldmem(&addr, &S390_lowcore.vmcore_info, sizeof(addr)))
 		return ptr;
 	memset(nt_name, 0, sizeof(nt_name));
 	if (copy_from_oldmem(&note, addr, sizeof(note)))
 		return ptr;
 	if (copy_from_oldmem(nt_name, addr + sizeof(note), sizeof(nt_name) - 1))
 		return ptr;
 	if (strcmp(nt_name, "VMCOREINFO") != 0)
 		return ptr;
 	vmcoreinfo = kzalloc_panic(note.n_descsz + 1);
 	if (copy_from_oldmem(vmcoreinfo, addr + 24, note.n_descsz))
 		return ptr;
 	vmcoreinfo[note.n_descsz + 1] = 0;
 	return nt_init(ptr, 0, vmcoreinfo, note.n_descsz, "VMCOREINFO");
 }

 /*
  * Initialize ELF header (new kernel)
  */
 static void *ehdr_init(Elf64_Ehdr *ehdr, int mem_chunk_cnt)
 {
 	memset(ehdr, 0, sizeof(*ehdr));
 	memcpy(ehdr->e_ident, ELFMAG, SELFMAG);
 	ehdr->e_ident[EI_CLASS] = ELFCLASS64;
 	ehdr->e_ident[EI_DATA] = ELFDATA2MSB;
 	ehdr->e_ident[EI_VERSION] = EV_CURRENT;
 	memset(ehdr->e_ident + EI_PAD, 0, EI_NIDENT - EI_PAD);
 	ehdr->e_type = ET_CORE;
 	ehdr->e_machine = EM_S390;
 	ehdr->e_version = EV_CURRENT;
 	ehdr->e_phoff = sizeof(Elf64_Ehdr);
 	ehdr->e_ehsize = sizeof(Elf64_Ehdr);
 	ehdr->e_phentsize = sizeof(Elf64_Phdr);
 	ehdr->e_phnum = mem_chunk_cnt + 1;
 	return ehdr + 1;
 }

 /*
  * Return CPU count for ELF header (new kernel)
  */
 static int get_cpu_cnt(void)
 {
 	int i, cpus = 0;

 	for (i = 0; zfcpdump_save_areas[i]; i++) {
 		if (zfcpdump_save_areas[i]->pref_reg == 0)
 			continue;
 		cpus++;
 	}
 	return cpus;
 }

 /*
  * Return memory chunk count for ELF header (new kernel)
  */
 static int get_mem_chunk_cnt(void)
 {
 	struct mem_chunk *chunk_array, *mem_chunk;
 	int i, cnt = 0;

 	chunk_array = get_memory_layout();
 	for (i = 0; i < MEMORY_CHUNKS; i++) {
 		mem_chunk = &chunk_array[i];
 		if (chunk_array[i].type != CHUNK_READ_WRITE &&
 		    chunk_array[i].type != CHUNK_READ_ONLY)
 			continue;
 		if (mem_chunk->size == 0)
 			continue;
 		cnt++;
 	}
 	kfree(chunk_array);
 	return cnt;
 }

 /*
  * Relocate pointer in order to allow vmcore code access the data
  */
 static inline unsigned long relocate(unsigned long addr)
 {
 	return OLDMEM_BASE + addr;
 }

 /*
  * Initialize ELF loads (new kernel)
  */
 static int loads_init(Elf64_Phdr *phdr, u64 loads_offset)
 {
 	struct mem_chunk *chunk_array, *mem_chunk;
 	int i;

 	chunk_array = get_memory_layout();
 	for (i = 0; i < MEMORY_CHUNKS; i++) {
 		mem_chunk = &chunk_array[i];
 		if (mem_chunk->size == 0)
 			break;
 		if (chunk_array[i].type != CHUNK_READ_WRITE &&
 		    chunk_array[i].type != CHUNK_READ_ONLY)
 			continue;
 		else
 			phdr->p_filesz = mem_chunk->size;
 		phdr->p_type = PT_LOAD;
 		phdr->p_offset = mem_chunk->addr;
 		phdr->p_vaddr = mem_chunk->addr;
 		phdr->p_paddr = mem_chunk->addr;
 		phdr->p_memsz = mem_chunk->size;
 		phdr->p_flags = PF_R | PF_W | PF_X;
 		phdr->p_align = PAGE_SIZE;
 		phdr++;
 	}
 	kfree(chunk_array);
 	return i;
 }

 /*
  * Initialize notes (new kernel)
  */
 static void *notes_init(Elf64_Phdr *phdr, void *ptr, u64 notes_offset)
 {
 	struct save_area *sa;
 	void *ptr_start = ptr;
 	int i;

 	ptr = nt_prpsinfo(ptr);

 	for (i = 0; zfcpdump_save_areas[i]; i++) {
 		sa = zfcpdump_save_areas[i];
 		if (sa->pref_reg == 0)
 			continue;
 		ptr = fill_cpu_elf_notes(ptr, sa);
 	}
 	ptr = nt_vmcoreinfo(ptr);
 	memset(phdr, 0, sizeof(*phdr));
 	phdr->p_type = PT_NOTE;
 	phdr->p_offset = relocate(notes_offset);
 	phdr->p_filesz = (unsigned long) PTR_SUB(ptr, ptr_start);
 	phdr->p_memsz = phdr->p_filesz;
 	return ptr;
 }

 /*
  * Create ELF core header (new kernel)
  */
 static void s390_elf_corehdr_create(char **elfcorebuf, size_t *elfcorebuf_sz)
 {
 	Elf64_Phdr *phdr_notes, *phdr_loads;
 	int mem_chunk_cnt;
 	void *ptr, *hdr;
 	u32 alloc_size;
 	u64 hdr_off;

 	mem_chunk_cnt = get_mem_chunk_cnt();

 	alloc_size = 0x1000 + get_cpu_cnt() * 0x300 +
 		mem_chunk_cnt * sizeof(Elf64_Phdr);
 	hdr = kzalloc_panic(alloc_size);
 	/* Init elf header */
 	ptr = ehdr_init(hdr, mem_chunk_cnt);
 	/* Init program headers */
 	phdr_notes = ptr;
 	ptr = PTR_ADD(ptr, sizeof(Elf64_Phdr));
 	phdr_loads = ptr;
 	ptr = PTR_ADD(ptr, sizeof(Elf64_Phdr) * mem_chunk_cnt);
 	/* Init notes */
 	hdr_off = PTR_DIFF(ptr, hdr);
 	ptr = notes_init(phdr_notes, ptr, ((unsigned long) hdr) + hdr_off);
 	/* Init loads */
 	hdr_off = PTR_DIFF(ptr, hdr);
 	loads_init(phdr_loads, ((unsigned long) hdr) + hdr_off);
 	*elfcorebuf_sz = hdr_off;
 	*elfcorebuf = (void *) relocate((unsigned long) hdr);
 	BUG_ON(*elfcorebuf_sz > alloc_size);
 }

 /*
  * Create kdump ELF core header in new kernel, if it has not been passed via
  * the "elfcorehdr" kernel parameter
  */
 static int setup_kdump_elfcorehdr(void)
 {
 	size_t elfcorebuf_sz;
 	char *elfcorebuf;

 	if (!OLDMEM_BASE || is_kdump_kernel())
 		return -EINVAL;
 	s390_elf_corehdr_create(&elfcorebuf, &elfcorebuf_sz);
 	elfcorehdr_addr = (unsigned long long) elfcorebuf;
 	elfcorehdr_size = elfcorebuf_sz;
 	return 0;
 }

 subsys_initcall(setup_kdump_elfcorehdr);
	/*
	* S390 kdump implementation
	*
	* Copyright IBM Corp. 2011
	* Author(s): Michael Holzheu <holzheu@linux.vnet.ibm.com>
	*/

	#include <linux/crash_dump.h>
	#include <asm/lowcore.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/gfp.h>
	#include <linux/slab.h>
	#include <linux/bootmem.h>
	#include <linux/elf.h>
	#include <asm/ipl.h>

	#define PTR_ADD(x, y) (((char *) (x)) + ((unsigned long) (y)))
	#define PTR_SUB(x, y) (((char *) (x)) - ((unsigned long) (y)))
	#define PTR_DIFF(x, y) ((unsigned long)(((char *) (x)) - ((unsigned long) (y))))

	/*
	* Copy one page from "oldmem"
	*
	* For the kdump reserved memory this functions performs a swap operation:
	* - [OLDMEM_BASE - OLDMEM_BASE + OLDMEM_SIZE] is mapped to [0 - OLDMEM_SIZE].
	* - [0 - OLDMEM_SIZE] is mapped to [OLDMEM_BASE - OLDMEM_BASE + OLDMEM_SIZE]
	*/
	ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
	size_t csize, unsigned long offset, int userbuf)
	{
	unsigned long src;

	if (!csize)
	return 0;

	src = (pfn << PAGE_SHIFT) + offset;
	if (src < OLDMEM_SIZE)
	src += OLDMEM_BASE;
	else if (src > OLDMEM_BASE &&
	src < OLDMEM_BASE + OLDMEM_SIZE)
	src -= OLDMEM_BASE;
	if (userbuf)
	copy_to_user_real((void __force __user ) buf, (void ) src,
	csize);
	else
	memcpy_real(buf, (void *) src, csize);
	return csize;
	}

	/*
	* Copy memory from old kernel
	*/
	static int copy_from_oldmem(void dest, void src, size_t count)
	{
	unsigned long copied = 0;
	int rc;

	if ((unsigned long) src < OLDMEM_SIZE) {
	copied = min(count, OLDMEM_SIZE - (unsigned long) src);
	rc = memcpy_real(dest, src + OLDMEM_BASE, copied);
	if (rc)
	return rc;
	}
	return memcpy_real(dest + copied, src + copied, count - copied);
	}

	/*
	* Alloc memory and panic in case of ENOMEM
	*/
	static void *kzalloc_panic(int len)
	{
	void *rc;

	rc = kzalloc(len, GFP_KERNEL);
	if (!rc)
	panic("s390 kdump kzalloc (%d) failed", len);
	return rc;
	}

	/*
	* Get memory layout and create hole for oldmem
	*/
	static struct mem_chunk *get_memory_layout(void)
	{
	struct mem_chunk *chunk_array;

	chunk_array = kzalloc_panic(MEMORY_CHUNKS * sizeof(struct mem_chunk));
	detect_memory_layout(chunk_array);
	create_mem_hole(chunk_array, OLDMEM_BASE, OLDMEM_SIZE, CHUNK_CRASHK);
	return chunk_array;
	}

	/*
	* Initialize ELF note
	*/
	static void nt_init(void buf, Elf64_Word type, void *desc, int d_len,
	const char *name)
	{
	Elf64_Nhdr *note;
	u64 len;

	note = (Elf64_Nhdr *)buf;
	note->n_namesz = strlen(name) + 1;
	note->n_descsz = d_len;
	note->n_type = type;
	len = sizeof(Elf64_Nhdr);

	memcpy(buf + len, name, note->n_namesz);
	len = roundup(len + note->n_namesz, 4);

	memcpy(buf + len, desc, note->n_descsz);
	len = roundup(len + note->n_descsz, 4);

	return PTR_ADD(buf, len);
	}

	/*
	* Initialize prstatus note
	*/
	static void nt_prstatus(void ptr, struct save_area *sa)
	{
	struct elf_prstatus nt_prstatus;
	static int cpu_nr = 1;

	memset(&nt_prstatus, 0, sizeof(nt_prstatus));
	memcpy(&nt_prstatus.pr_reg.gprs, sa->gp_regs, sizeof(sa->gp_regs));
	memcpy(&nt_prstatus.pr_reg.psw, sa->psw, sizeof(sa->psw));
	memcpy(&nt_prstatus.pr_reg.acrs, sa->acc_regs, sizeof(sa->acc_regs));
	nt_prstatus.pr_pid = cpu_nr;
	cpu_nr++;

	return nt_init(ptr, NT_PRSTATUS, &nt_prstatus, sizeof(nt_prstatus),
	"CORE");
	}

	/*
	* Initialize fpregset (floating point) note
	*/
	static void nt_fpregset(void ptr, struct save_area *sa)
	{
	elf_fpregset_t nt_fpregset;

	memset(&nt_fpregset, 0, sizeof(nt_fpregset));
	memcpy(&nt_fpregset.fpc, &sa->fp_ctrl_reg, sizeof(sa->fp_ctrl_reg));
	memcpy(&nt_fpregset.fprs, &sa->fp_regs, sizeof(sa->fp_regs));

	return nt_init(ptr, NT_PRFPREG, &nt_fpregset, sizeof(nt_fpregset),
	"CORE");
	}

	/*
	* Initialize timer note
	*/
	static void nt_s390_timer(void ptr, struct save_area *sa)
	{
	return nt_init(ptr, NT_S390_TIMER, &sa->timer, sizeof(sa->timer),
	KEXEC_CORE_NOTE_NAME);
	}

	/*
	* Initialize TOD clock comparator note
	*/
	static void nt_s390_tod_cmp(void ptr, struct save_area *sa)
	{
	return nt_init(ptr, NT_S390_TODCMP, &sa->clk_cmp,
	sizeof(sa->clk_cmp), KEXEC_CORE_NOTE_NAME);
	}

	/*
	* Initialize TOD programmable register note
	*/
	static void nt_s390_tod_preg(void ptr, struct save_area *sa)
	{
	return nt_init(ptr, NT_S390_TODPREG, &sa->tod_reg,
	sizeof(sa->tod_reg), KEXEC_CORE_NOTE_NAME);
	}

	/*
	* Initialize control register note
	*/
	static void nt_s390_ctrs(void ptr, struct save_area *sa)
	{
	return nt_init(ptr, NT_S390_CTRS, &sa->ctrl_regs,
	sizeof(sa->ctrl_regs), KEXEC_CORE_NOTE_NAME);
	}

	/*
	* Initialize prefix register note
	*/
	static void nt_s390_prefix(void ptr, struct save_area *sa)
	{
	return nt_init(ptr, NT_S390_PREFIX, &sa->pref_reg,
	sizeof(sa->pref_reg), KEXEC_CORE_NOTE_NAME);
	}

	/*
	* Fill ELF notes for one CPU with save area registers
	*/
	void fill_cpu_elf_notes(void ptr, struct save_area *sa)
	{
	ptr = nt_prstatus(ptr, sa);
	ptr = nt_fpregset(ptr, sa);
	ptr = nt_s390_timer(ptr, sa);
	ptr = nt_s390_tod_cmp(ptr, sa);
	ptr = nt_s390_tod_preg(ptr, sa);
	ptr = nt_s390_ctrs(ptr, sa);
	ptr = nt_s390_prefix(ptr, sa);
	return ptr;
	}

	/*
	* Initialize prpsinfo note (new kernel)
	*/
	static void nt_prpsinfo(void ptr)
	{
	struct elf_prpsinfo prpsinfo;

	memset(&prpsinfo, 0, sizeof(prpsinfo));
	prpsinfo.pr_sname = 'R';
	strcpy(prpsinfo.pr_fname, "vmlinux");
	return nt_init(ptr, NT_PRPSINFO, &prpsinfo, sizeof(prpsinfo),
	KEXEC_CORE_NOTE_NAME);
	}

	/*
	* Initialize vmcoreinfo note (new kernel)
	*/
	static void nt_vmcoreinfo(void ptr)
	{
	char nt_name[11], *vmcoreinfo;
	Elf64_Nhdr note;
	void *addr;

	if (copy_from_oldmem(&addr, &S390_lowcore.vmcore_info, sizeof(addr)))
	return ptr;
	memset(nt_name, 0, sizeof(nt_name));
	if (copy_from_oldmem(&note, addr, sizeof(note)))
	return ptr;
	if (copy_from_oldmem(nt_name, addr + sizeof(note), sizeof(nt_name) - 1))
	return ptr;
	if (strcmp(nt_name, "VMCOREINFO") != 0)
	return ptr;
	vmcoreinfo = kzalloc_panic(note.n_descsz + 1);
	if (copy_from_oldmem(vmcoreinfo, addr + 24, note.n_descsz))
	return ptr;
	vmcoreinfo[note.n_descsz + 1] = 0;
	return nt_init(ptr, 0, vmcoreinfo, note.n_descsz, "VMCOREINFO");
	}

	/*
	* Initialize ELF header (new kernel)
	*/
	static void ehdr_init(Elf64_Ehdr ehdr, int mem_chunk_cnt)
	{
	memset(ehdr, 0, sizeof(*ehdr));
	memcpy(ehdr->e_ident, ELFMAG, SELFMAG);
	ehdr->e_ident[EI_CLASS] = ELFCLASS64;
	ehdr->e_ident[EI_DATA] = ELFDATA2MSB;
	ehdr->e_ident[EI_VERSION] = EV_CURRENT;
	memset(ehdr->e_ident + EI_PAD, 0, EI_NIDENT - EI_PAD);
	ehdr->e_type = ET_CORE;
	ehdr->e_machine = EM_S390;
	ehdr->e_version = EV_CURRENT;
	ehdr->e_phoff = sizeof(Elf64_Ehdr);
	ehdr->e_ehsize = sizeof(Elf64_Ehdr);
	ehdr->e_phentsize = sizeof(Elf64_Phdr);
	ehdr->e_phnum = mem_chunk_cnt + 1;
	return ehdr + 1;
	}

	/*
	* Return CPU count for ELF header (new kernel)
	*/
	static int get_cpu_cnt(void)
	{
	int i, cpus = 0;

	for (i = 0; zfcpdump_save_areas[i]; i++) {
	if (zfcpdump_save_areas[i]->pref_reg == 0)
	continue;
	cpus++;
	}
	return cpus;
	}

	/*
	* Return memory chunk count for ELF header (new kernel)
	*/
	static int get_mem_chunk_cnt(void)
	{
	struct mem_chunk chunk_array, mem_chunk;
	int i, cnt = 0;

	chunk_array = get_memory_layout();
	for (i = 0; i < MEMORY_CHUNKS; i++) {
	mem_chunk = &chunk_array[i];
	if (chunk_array[i].type != CHUNK_READ_WRITE &&
	chunk_array[i].type != CHUNK_READ_ONLY)
	continue;
	if (mem_chunk->size == 0)
	continue;
	cnt++;
	}
	kfree(chunk_array);
	return cnt;
	}

	/*
	* Relocate pointer in order to allow vmcore code access the data
	*/
	static inline unsigned long relocate(unsigned long addr)
	{
	return OLDMEM_BASE + addr;
	}

	/*
	* Initialize ELF loads (new kernel)
	*/
	static int loads_init(Elf64_Phdr *phdr, u64 loads_offset)
	{
	struct mem_chunk chunk_array, mem_chunk;
	int i;

	chunk_array = get_memory_layout();
	for (i = 0; i < MEMORY_CHUNKS; i++) {
	mem_chunk = &chunk_array[i];
	if (mem_chunk->size == 0)
	break;
	if (chunk_array[i].type != CHUNK_READ_WRITE &&
	chunk_array[i].type != CHUNK_READ_ONLY)
	continue;
	else
	phdr->p_filesz = mem_chunk->size;
	phdr->p_type = PT_LOAD;
	phdr->p_offset = mem_chunk->addr;
	phdr->p_vaddr = mem_chunk->addr;
	phdr->p_paddr = mem_chunk->addr;
	phdr->p_memsz = mem_chunk->size;
	phdr->p_flags = PF_R \| PF_W \| PF_X;
	phdr->p_align = PAGE_SIZE;
	phdr++;
	}
	kfree(chunk_array);
	return i;
	}

	/*
	* Initialize notes (new kernel)
	*/
	static void notes_init(Elf64_Phdr phdr, void *ptr, u64 notes_offset)
	{
	struct save_area *sa;
	void *ptr_start = ptr;
	int i;

	ptr = nt_prpsinfo(ptr);

	for (i = 0; zfcpdump_save_areas[i]; i++) {
	sa = zfcpdump_save_areas[i];
	if (sa->pref_reg == 0)
	continue;
	ptr = fill_cpu_elf_notes(ptr, sa);
	}
	ptr = nt_vmcoreinfo(ptr);
	memset(phdr, 0, sizeof(*phdr));
	phdr->p_type = PT_NOTE;
	phdr->p_offset = relocate(notes_offset);
	phdr->p_filesz = (unsigned long) PTR_SUB(ptr, ptr_start);
	phdr->p_memsz = phdr->p_filesz;
	return ptr;
	}

	/*
	* Create ELF core header (new kernel)
	*/
	static void s390_elf_corehdr_create(char *elfcorebuf, size_t elfcorebuf_sz)
	{
	Elf64_Phdr phdr_notes, phdr_loads;
	int mem_chunk_cnt;
	void ptr, hdr;
	u32 alloc_size;
	u64 hdr_off;

	mem_chunk_cnt = get_mem_chunk_cnt();

	alloc_size = 0x1000 + get_cpu_cnt() * 0x300 +
	mem_chunk_cnt * sizeof(Elf64_Phdr);
	hdr = kzalloc_panic(alloc_size);
	/* Init elf header */
	ptr = ehdr_init(hdr, mem_chunk_cnt);
	/* Init program headers */
	phdr_notes = ptr;
	ptr = PTR_ADD(ptr, sizeof(Elf64_Phdr));
	phdr_loads = ptr;
	ptr = PTR_ADD(ptr, sizeof(Elf64_Phdr) * mem_chunk_cnt);
	/* Init notes */
	hdr_off = PTR_DIFF(ptr, hdr);
	ptr = notes_init(phdr_notes, ptr, ((unsigned long) hdr) + hdr_off);
	/* Init loads */
	hdr_off = PTR_DIFF(ptr, hdr);
	loads_init(phdr_loads, ((unsigned long) hdr) + hdr_off);
	*elfcorebuf_sz = hdr_off;
	elfcorebuf = (void ) relocate((unsigned long) hdr);
	BUG_ON(*elfcorebuf_sz > alloc_size);
	}

	/*
	* Create kdump ELF core header in new kernel, if it has not been passed via
	* the "elfcorehdr" kernel parameter
	*/
	static int setup_kdump_elfcorehdr(void)
	{
	size_t elfcorebuf_sz;
	char *elfcorebuf;

	if (!OLDMEM_BASE \|\| is_kdump_kernel())
	return -EINVAL;
	s390_elf_corehdr_create(&elfcorebuf, &elfcorebuf_sz);
	elfcorehdr_addr = (unsigned long long) elfcorebuf;
	elfcorehdr_size = elfcorebuf_sz;
	return 0;
	}

	subsys_initcall(setup_kdump_elfcorehdr);